Monogamous

[Dave Paprocki]

Mating with but one of the opposite sex; -- said of
birds and mammals.

[Jason Yan]

The only [civilized] [way to be].
The [happiest] way to be.
One person for life.

[Luis Fok]

A relationship of trust where a partner is dedicated to another single partner, or at least apparently to the [extent] of being in the same [zip] code, or how bored some [losers] who cant control themselves get.

[Renato]

The act of being [committed] to [only one] [sexual partner].

[Renato]

Involving marriage to one person at a time.

[Michiko]

[The condition] of only [playing] one game or one [genre].

[Tracie Lynn]

having a sexual relationship or marriage with only one person at a time: